Numerous systems, devices and methods are known for brachytherapy use. Some of these incorporate balloons to achieve and maintain proper placement and/or as a component of radiation material delivery. Some incorporate multiple delivery paths for the radiation material.
Radiation oncology brachytherapy practitioners and researchers have developed various devices, systems and methods, each typically being designed for a specific diseased body organ or part and/or for one or more treatment regimens. Whether the treatment regimen is a one-step or multi-step protocol, it is important to maintain a good balance among radiation dosage, placement and timing. Timing can involve treatment and non-treatment intervals that vary depending upon the oncology protocol to be followed.
Carcinoma treatment procedures can follow a protocol calling for a series of multiple implants, such as when following high dose rate (HDR) brachytherapy. At times, the oncologist may choose to use a low dose rate (LDR) brachytherapy regimen, typically based on cesium delivery as 137Cs. For HDR brachytherapy regimens 192Ir is frequently used because of its high specific activity. Other isotopes are available and used as warranted. The degree of treatment is measured in terms of units of radiation exposure (in roentgens or Gray or Gy), and often these are prescribed at specific points. Details in this regard are known to radiation oncologists, medical physicists and other medical professionals experienced in brachytherapy. An objective often is to provide reasonably constant and predictable dose rates at each location at which the isotopes are applied.
Accordingly, it is clear that intracavitary radiation treatment and other brachytherapy that is not intracavitary, such as those gaining access through a surgical opening or access location, need to be exacting and specific in each of dose rates, durations and radiation target locations, for example. In addition, the closeness of tissues not intended to be irradiated should be taken into consideration. For example, in intrauterine treatment it is important to minimize, if not eliminate, radiation exposure to the bladder and rectum. Generally, brachytherapy devices are visible under X-ray images in order to ensure intended placement and to allow the medical physicist or professional to generate a radiation treatment plan specific for this placement and for the particular anatomy and disease location and severity for the particular patient and for this treatment event.
It will be appreciated that brachytherapy delivery systems can be used in treatments that are applied manually or remotely using remote afterloading systems. In remote afterloading systems, the radioactive materials are delivered from a safely contained source by way of hollow tubes to hollow treatment portions or locations. Radioactive material can be in the form of wires, seeds or other forms. In such systems, the radioactive material is typically delivered via remote control, such as by operation of a motor, after the medical professionals all are removed from the treatment room. Such remote delivery equipment can move the radioactive dose into the applicator already positioned within the body cavity.